Temperature-dependent electrical characteristics of selectively crystallized InGaOx gate-all-around nanosheet FETs

We investigate the temperature-dependent electrical characteristics and bias-temperature-instability (BTI) of InGaOx gate-all-around (GAA) nanosheet FETs with different HfO 2 thicknesses. The 5 nm-HfO 2 GAA device shows higher transconductance (1550 μS μm −1 ) and effective mobility (52 cm 2 Vs −1 ) than the 7 nm-HfO 2 device. The performance improvement arises from increased gate-capacitance and mobility enhancement. At low temperatures, subthreshold swing saturates due to band-tail-states effects. The 5 nm-HfO 2 device shows more pronounced phonon-like temperature dependence than 7 nm-HfO 2 device, suggesting a lower Coulomb-scattering contribution. Positive-BTI shows comparable negative V th shifts, whereas negative-BTI shows negligible shifts, against bottom-gate devices.